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Homework Help: Project on transistors and how they work

  1. Jan 13, 2006 #1
    Hey, I'm doing a project on transistors and i need some help on how they work. So far I know that a transistor can amplify the current of the flow of electricity and contains 3 layers 1 being Silicon. Please, I need additional information on transistors (like an hour worth of info).
  2. jcsd
  3. Jan 13, 2006 #2
    You need to be a bit more specific. What kind of transistor are you looking for (bipolar, MOSFET)? Here are some examples. If you just google for MOSFET, you will find many good sites on this topic.

  4. Jan 13, 2006 #3
    Actually I am being specific on what i need more info on transistors. All the transistors which have silicon layer on it. (marlon thanks for the info on different wiring transistor, I didn't know about that.)
  5. Jan 13, 2006 #4
    No you are not since every transistor has silicon in it somehow. Even the transistors based upon the Germanium wafers actually exhibit the same structure as any other silicon based transistor. You cannot make a classification in transistor-structure purely based upon what layers are used. That was my point.

    Here is another site i can really recommend.

  6. Jan 13, 2006 #5


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    Discuss the bipolar junction transistor (BJT) which is a doped-silicon device with three regions (NOT layers). Here's a wealth of information. Please ask specific questions and we'll be happy to provide additional information.


    - Warren
  7. Jan 14, 2006 #6
    Alright. I need some info that a grade 11 student would understand, like different shapes, sizes and how they work basically. I'd like to see The most common of transistors that grade 11's would mostly see.
    Last edited: Jan 14, 2006
  8. Jan 14, 2006 #7


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    If you are new to this subject, you should start out from the band theory of solids and how we apply that to semiconductors.
    http://hyperphysics.phy-astr.gsu.edu/hbase/solids/band.html" [Broken]

    Then you can understand how pure semiconductors or intrinsic semiconductors conduct electricity.

    http://hyperphysics.phy-astr.gsu.edu/hbase/solids/intrin.html" [Broken]

    Then comes doping and the p-type and n-type semiconductors
    http://hyperphysics.phy-astr.gsu.edu/hbase/solids/dope.html" [Broken]

    Next is the p-n junction and what happends when the junction is forward biased and reversed bias. This is key to understanding diodes and transistors.

    http://hyperphysics.phy-astr.gsu.edu/hbase/solids/pnjun.html" [Broken]

    This will make it easier for you to understand how some diodes (like the p-n junction diode) and transistors(like the p-n-p and n-p-n junction transistors) work.

    As chroot said, if you have any difficulties or questions following the material, you can ask here.

    Finally, for some basic applications of transistors, you can check out how the transistor is used in an Amplifier circuit and how it is used in an Oscillator circuit.
    Logic gates (like AND, OR and NOT) can be implemented using diodes and transistors. You might want to take a look at that as well.
    Last edited by a moderator: May 2, 2017
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